As the advancement of the electronic information industry, various electronic elements, such as central processing units (CPUs), now have higher performance but also produce more heat during operation thereof. A thermal module composed of heat radiating fins and cooling fans is no longer sufficient for effectively dissipating the large amount of heat generated by the high-performance electronic elements. Currently, a heat pipe is a key element being widely used particularly in notebook computers, tablet PCs, smart watches, wearable smart devices and the like for heat transfer. The heat pipe is a passive heat transfer element with excellent heat transfer efficiency. With the two-phase conversion between vapor and liquid inside it, the heat pipe has heat transfer ability several hundred times higher than that of copper of the same size. When being used to transfer heat, the heat pipe has the advantages of fast response and low thermal resistance. Therefore, various high-performance thermal modules are developed by incorporating heat pipes and other relevant products thereinto for suitably solving the heat dissipation problem of the high-performance electronic products.
The conventional method for sealing a heat pipe includes the steps of sealing one end of the heat pipe; evacuating the heat pipe via an opposite open end thereof before filling a working fluid into the heat pipe via the open end; drawing and reducing the open end to form a reducing section; and sealing the reducing section of the heat pipe by argon welding. Since the reducing section of the conventional heat pipe does not provide the heat transfer function, it becomes an ineffective portion to adversely affect the heat transfer efficiency of the heat pipe. Moreover, the sealed reducing section must be long enough to prevent the heat pipe from leaking. However, the long reducing section, i.e. the ineffective portion, not only shortens the effective length of the heat pipe for heat transfer, but also occupies a lot of space particularly when the heat pipe is mounted in a smart mobile device, such as a smart watch or a smartphones, disadvantageously preventing the smart mobile device from being further reduced in dimensions.
It is therefore tried by the inventor to develop an improved method for removing the ineffective portion from the heat pipe, allowing the heat pipe to have increased heat transfer efficiency and occupy less space.